2010/12/09 by Meyer, Jennifer Donovan, J. H. van Gorkom, David Schiminovich +2
Engineering · Environmental Science · Physics and Astronomy · #Astrophysics and Star Formation Studies #CCD and CMOS Imaging Sensors #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Impact of Light on Environment and Health
paper · pdf · doi:10.48550/arxiv.1012.2161
openalex publication_date 2010/12/09 · openalex created_date 2022/10/02 · openalex updated_date 2026/07/28
We present an analysis of ultraviolet (UV) emission in the outer regions of a\nlocal, volume-limited sample of 56 early-type galaxies, where H\α\nemission from massive star formation is typically absent. We find excess faint\nNUV emission in the environments of our early-type galaxies compared to blank\nsky measured in the same tiles, indicating that the excesses are not due to\nbackground contamination. We do not observe corresponding faint FUV excesses.\nFaint NUV excesses increase with galaxy luminosity and are not correlated with\nthe presence or absence of HI in the environments of these galaxies. The faint\nNUV excesses in the outskirts of early-type galaxies can be interpreted as\nbeing due to star formation at or above a few \× 10-5 M odot yr-1 kpc-2;\nstar formation at this rate can create a few percent of the mass of an\nearly-type galaxy in a Gyr. Faint early types (with MB > -21.3) have on average\nfour times as many bright UV sources within 30 kpc compared to bright early\ntypes (with MB < -21.3). The peak of the source distribution detected around\nfaint early types is less luminous and slightly bluer than the peak of the\nsources detected around bright early types, indicating that early types with MB\n> -21.3 are more actively building up their mass with young stars. The spatial\ndistribution of bright sources around all early types increases approximately\nlinearly out to 20 kpc and subsequently flattens.\n